There are substances with high environment risk, such as drugs of high toxicity, which are normally enclosed in small sealed bottles, having blocked on the mouth or opening thereof a rubber plug which can be perforated by a needle applied on a syringe in order to draw the drug or substance, in the case after injection of a solvent into the bottle, for later use of such a substance, for example for intravenous transfusion, if a drug is involved.
As mentioned, some of these substance are highly toxic or of high environment risk, so that it is highly desirable to prevent that even minimal small drops of the drug or substance would contaminate the outer ambient or come in contact with the skin of the person drawing the substance from the bottle.
At present, drawing of the substance or drug from a bottle of this type occurs by making the drug drawing person to wear rubber gloves and paying maximum attention in transfer step of the syringe with needle from the bottle to the successive use. There are also quite complex apparatuses, practically comprising water-tight chambers in which liquid drawing is effected by operating the syringe and bottle from outside, commonly used in large hospitals for handling high risk substances. However, there is no warranty of avoiding an outside dripping of the liquid (substance or drug) between the drawing step from the bottle and the direct use step.
Many kinds of devices have been proposed for overcoming the above referred drawbacks.
The U.S. Pat. Nos. 3,392,726; 3,826,260; and 3,995,630 and the German Pat. No. 1,166,419 disclose devices suitable to connect an injection syringe to a vial which contains a medicament. The devices include a first member which is fixedly or detachably connected to the vial and a second member which can be connected to the syringe, the two members forming a telescopic assembly such that when the syringe is pressed toward the vial, a hollow needle perforates one or more seals thereby communicating with and between the interiors of the syringe and the vial. It can be easily seen that no provision is made for preventing accidental telescoping movement of the mentioned assembly and especially that no means are provided for avoiding the risk of contamination or the like when the two members are disconnected the one from the other in order to administer into a patient the dissolved medicament.
The U.S. Pat. No. 3,336,924 concerns a device which is similar to those mentioned hereabove, but in which the needle is protected by a covering which is fractured on telescoping movement of the parts. However, this device does not avoid the risk of contamination after the mixed vial contents has been aspired into the syringe and the syringe has been separated from the vial.
The U.S. Pat. No. 2,847,995 and the Norwegian Pat. No. 141,537 disclose transfusion needle sheets maintaining the needle in properly sterile condition for indefinite periods of time.